Method of manufacturing a writing or drawing nib



May12,.1970 H. Kol-:LICHEN 3,5w934 METHOD OF MANUFACTURING A WRITING OR DRAWING NIB Filed Feb. 1, 196'? Fig. 5y

United *Stan-:s- Patent O F 48,354 Int. Cl. B23p 17/00, 7l/00; B21d 39/00 U.S. Cl. 29-419 2 Claims ABSTRACT OF THE DISCLOSURE Writing or drawing nibs consisting of a bundle of metal fibers or threads within a liquid-tight metal covering. The metalic cover for the nibs may be provided by nickel or chromium coatings, or by mounting the fibers within a steel tube. The thus covered fiber bundle may additionally be covered with a protective epoxy resin coating.

So called felt pens have been in use for some time. As is known, these writing instruments are fitted with a felt or synthetic-fibre nib lmade by a special method. Such synthetic-fibre nibs are made -by impregnating an unprocessed synthetic-fibre bundle in a synthetic resin solution, wiping the excess liquid from the synthetic fibres and then passing the suitably shaped synthetic fibre bundle through a drying device to evaporate a solvent contained in the synthetic resin by means of a hot-air fan. The already dried fibre bundle is then brought to its intended diameter in heating and 'shaping means. The evaporation of the solvent in the synthetic resin gives rise to free spaces ibetween Vthe irregularly intertwined synthetic fibres, and said'free spaces are filled with liquid by capillary action when the nib is connected to an ink or liquid container and thus traversed by liquid during the writing and drawing operation.

Synthetic-fibre nibs made in this way have however a very limited life due to their low wear resistance.

Furthermore, the synthetic-resin impregnation lwhich is intended to hold the synthetic fibres together in the form of a pencil can only withstand small writing pressures and as a result the synthetic fibres spread and separate when relatively high writing pressures are used.

A further disadvantage of these synthetic-fibre nibs has been found in practice to be evaporation of residual writing liquid inthe outer zone of the nib body, as the result of which drying -may extend from the outer end zone of the fibre nib body up to the nib point.

The object of the invention is to provide felt or fibre pens which have a substantially greater wear resistance and resistance to pressure than the known syntheticfibre pens described above, and which at the same time considerably reduce the possibility of the ink evaporation.

It was surprisingly possibly to achieve this object by constructing the fibre pens substantially from at least one bundle of thin metal fibres and a liquid-tight preferably metallic covering surrounding the metal fibres. The metal fibres and the covering are preferably made from corrosion-resistant materials, for example corrosion-resistant refined steel and nickel. The covering may also be provided with a hard-chrome coating to increase its wear resistance. Instead of the bundles of metal fibres, metal threads or bundles assembled therefrom may be used.,

The liquid-tight metal coverings increase the strength of the fibre pens and confine the emergence of the writing liquid to the working point of the fibre nibs, i.e. to their end face which slides on the writing or drawing paper.

p ice Evaporation of the solvent of the Indian ink is thus prevented along the cylindrical outer surface of the fibre pen and the use of rapid-drying inks or Indian inks made possible for fibre pens.

Since the metal fibres have a higher mechanical strength than synthetic fibres, they can project at the nib of the bre pen more than synthetic fibres without fear of brush-like spreading of the fibre nibs under the writing pressure, which is a known disadvantage of syntheticfibre pens. The metal fibres combined with the metal covering thus make possible a more elastic writing than with the known synthetic-fibre pens.

The wear resistance of synthetic substances and the fibres and coverings made therefrom is substantially less than the wear resistance of metal fibres and metal coverings, especially of such made from stainless and corrosionresistant refined steels. Metal-fibre pens thus have a higher wear reistance and longer life than synthetic-fibre pens.

The thin metal fibres or threads preferably to be used may if necessary be slightly corrugated or curled for the fibre bundles or skeins required in the metal-fibre pens.

The liquid-tight coverings may be applied to the fibre llbundles or skeins by galvanic deposition, vapour deposi- Commercial refined-steel fibres approximately 10 to 50,1 in diameter are first combined to form bundles of predetermined outer diameter and of the desired length, and then degreased electrolytically in an alkali bath, the fibre bundle lbeing connected as cathode and subjected to a current density of approximately 10 a. per dm.2 for `about 2 minutes at room temperature. The fibre nibs are thereafter thoroughly rinsed with water, neutralized with dilute hydrochloric acid and then again thoroughly rinsed with water.

The fibre bundles thus cleaned are then transferred to a galvanic bath for depositing nickel. A suitable bath for this purpose is for example one which contains the following additives per litre of water:

G. Niso4-5H2o 175 KF l5 HB03 1o Nazso4 10 NaCl 5 H2804 7.5 Butinediol 5 This bath operates at a pH value of about 4.8. In it, the fibre bundles are connected as cathode and subjected y in the centre to about 7 to 9 a. per dm.2 at 50 C. With the irregular surface of the fibre bundles however, the local load can lie between 5 to l2 a. per dm.2 at the start of the nickel depositing.

Under the above conditions, coverings of any desired thickness may be deposited. The desired thickness of the covering may be regulated by varying the deposition time. Nickel layers of approximately 12p thickness may be deposited per hour from the nickel bath used per a./dm.2 current density. Under the conditions described above,

thethicknesses of the nickel layers deposited on the fibre bundles is approximately 85 to 105,1. after one hour of galvanic treatment. With increasing thickness the surface of the covering becomes increasingly plane, so that after only a covering of about 15G/r the original surface of the fibre bundle inserted can hardly be recognized.

For the galvanic deposition of coverings of nickel described, counter electrodes (anodes) which also consist of nickel and which surround the fibre bundles cylindrically are used to deposit the galvanic covering uniformly about the fibre bundle. It is however also possible to use fiat nickel electrodes and to rotate the fibre bundles about their own axis during deposition.

In this method, when very thin metal fibres are used only the outer fibres of the bundle are coated `with nickel and no nickel is deposited on the fibres disposed inside the bundle and on the intermediate spaces between them.

When using thicker metal fibres or threads, particularly with a low packing density, nickel may also be deposited on the inner fibres and in the intermediate spaces. This may however be avoided by surrounding these fibre bundles before depositing the covering with a layer of thin fibres.

If a very high wear resistance is desired, a hardchromium layer about to 10a thick may also be applied to it. For the galvanic depositing of this thin hardchromium layer baths are used which contain in addition to water for example 250 g. CrO3 and 2.5 g. H2504 per litre of solution. The nickel-plated fibre bundles or fibre nibs are connected as cathode and subjected at 50 to 55 C. to about 50 a./dm.2. The material used for the anode is lead containing also small amounts (less than 1%) of antimony. In this case too, the anodes are made tubular and put over the nickel-plated fibre nibs. It is however also possible to use flat anodes and rotate the fibre nibs as the chromium is deposited. To deposit chromium in the aforementioned thickness the the operation must be carried out for about 8.5 to 17 minutes under the conditions described.

Method II The bundle consisting of irregularly intertwined steel fibres as in Method I is provided with a liquid-tight metal outer protective layer in a high-vacuum vapourization apparatus. The metal layer deposited is thick enough to hold the steel fibres together mechanically.

With this method, a metallic layer may be vapourdeposited onto the already finished fibre nib and nib point in the high vacuum. It is however also possible to deposit the metallic layer by vapourization on a steelfibre bundle of greater length in the high vacuum and then to cut the bundle into individual nib lengths.

Method III In this method, the steel-fibre bundle is passed after known pretreatment (degreasing) through a heated trough containing conventional liquid metallic solder, the solder forming a metallic protective covering in the outer zone of the steel-fibre bundle. After pretreating the fibres with the solder, the steel-fibre bundle is drawn through a die-like preheated nozzle, wiping of the excess solder and bringing the bundle to the desired diameter. The method is controlled such that the solder is deposited only in the outer edge zone of the fibre bundle in the form of a covering, without interfering with the capillary inner spaces of the steel-fibre bundle.

Pencil-shaped fibre nibs of predetermined length may then be cut from the finished steel-fibre bundle.

Method IV The steel-fibre bundle is given a liquid-tight covering which consists of a metal tube, a very thin-walled but corrosion-resistant steel tube of high strength preferably being used. The skein-like steel fibres irregularly intertwined are drawn relatively loosely into this metal tube. The thin-Walled steel tube with the steel-fibre bundle disposed therein is then drawn through an extremely hard die made in the form of a draw-plate and consisting of imitation precious stone or the like, reducing the outer and inner diameters of the steel tube at the same time. The steel-fibre bundle on the inside is thereby held suitably firmly; although the steel fibres are pressed strongly enough together to ensure that they are held xed in the tubular casing, the capillary intermediate spaces remain.

A modification of this method is to roll a tube round the steel fibres. lIn this operation, the steel-fibre bundle is inserted in a half-open pre-rolled metal tube. The tube is thereafter also drawn through 'a nozzle-shaped die and brought to a predetermined outer diameter. The capillary steel-fibre body sits firmly inside the tube in this case as well, but the tube has a seam along its entire length. The steel tube described above is however a seamless predrawn tube.

Method V In this method, a liquid-light plastic covering is injection moulded around the skein-like preformed steel fibres in an injection mould. For this purpose, plastics of high wear resistance are preferably used. This method is particularly suited to fibre nibs of relatively large diameter.

Method VI In this case, the outer zone of the steel-fibre bundle is covered by applying a layer of lacquer adhesive, preferably with an epoxy resin base. This is done by dipping the steel-fibre into the corresponding plastic liquid and then wiping off the excess amount of the covering substance by means of a nozzle-shaped device.

The drawings show various examples of embodiment of drawing and writing nibs made according to the invention.

FIG. l is a longitudinal section through such a nib, in which metal fibres, especially steel fibres 1, are combined irregularly to form a bundle and provided with a covering layer 2 which extends only into the outer zone of the bundle and leaves its capillary inner spaces free. The fibre nib so formed is ground at the lower end 3 to a point, and -a quick-drying ink is supplied to its upper end face from an ink container (not shown). The covering layer 2 may be produced by galvanic methods, by vapour-deposition, by solder coating, or finally by injection-molding plastic yaround the bundle or by dipping into a plastic liquid.

FIG. 2 shows a similar fibre nib which is not of circular cross-section as in FIG. 1 but of rectangular cross-section. The nib 31 accordingly forms a rectangular surface ywhich is suited to the production of wide lines.

FIG. 3 shows 'a longitudinal section through a fibre nib which is of circular cross-section as in FIG. 1 but which is reduced in diameter at the front end at 41. This fibre nib is particularly suitable for so called Indian-ink pens which are used in conjunction with writing or drawing stencils. In this case, the writing liquid emerges from the lower end face of the nib end 41. The covering l-ayer 4 may be produced by one of the methods described.

FIG. 4 shows a nib which is held in the manner of a fountain pen 'when in use and which like the nibs described above consists of a covered fibre bundle. The covering is interrupted at 5 so that the steel-fibre bundle is exposed at this point and the ink can emerge at this exposed surface.

FIG. 5 shows anauy a fibre nib in which the steel-'abre bundle is held in a steel tube 6 according to Method IV, and the nib is ground, in a preferred form, semicircularly at 32; this embodiment is particularly suited to Indian-ink pins which are used in conjunction with stencils and the I claim:

1. The method of manufacturing a writing or drawing nib comprising the steps of forming a metal fibre bundle of irregularly intertwined'metal fibers, inserting said fibre bundle into a metal tube vlich will serve as a 1iquid- References Cited tight covering therefor and drawing the metal tube UNITED STATES PATENTS through a die which reduces the outer and inner diame- 186,707 1/1877 Blunt 401 198 ters of the tube to rmly hold the fiber bundle in place 1,463,015 7/ 1923 Guay 29-517 X While permitting capillary intermediate spaces to remain. 5 118391964 1/1932 Harvey 29-517 X 2. The method of'manufacturing a writing or drawing Vtnbe-n. 29-517 X mb as defined 1n cla1m 1 whereln said bre bundle is 1n- 3,361,516 1/1968 Rigondaud serted into a half open, pre-rolled metal tube which, after 10 having been drawn through the die for reducing the CHARLIE T' MOON Pnmary Exammer outer land inner diameters thereof, is closed along a longi- U.S. Cl. X.R. tudinal seam. 29-509, 517, 520; 401-198 

